Exercise may not cancel out drinking risks

DEAR DOCTOR: I just read about a study that says exercise cancels out alcohol’s higher risk of death from cancer. Is it possible that I can walk off the cancer risk of the cocktail I have each night after dinner?

DEAR READER: In this study, researchers in England looked at a decade of medical data collected from 36,370 women and men, all 40 or older. They sorted the study subjects by how much alcohol they consumed and by how much they exercised.

Not surprisingly, they found a statistical link between “hazardous drinking” and an increased risk of death from all causes, including cancer. In this study, hazardous drinking was defined as 8 to 20 servings of alcohol per week for women, and 21 to 49 servings of alcohol for men.

Then the researchers included exercise as a variable in their calculations. They found that among people who spent at least 150 minutes per week doing moderate aerobic activity, like a brisk walk, the mortality rate due to cancer dropped. This proved to be true even among the heavier drinkers, as long as they exercised.

On its face this seems to suggest that exercise can cancel out the elevated risk of cancer due to drinking. But this is what’s known as an observational study. That means the study is based solely on data collected from the same subjects over a period of time.

While studies like these are useful for pointing out the existence of certain patterns based on the information at hand, they can’t be used to prove cause and effect. The level of exercise among the drinkers is just one among countless variables that can play a role in whether someone goes on to get cancer.

What this study does do is add to the significant body of existing evidence that exercise plays a role in good health. Exercising may not automatically equal risk-free drinking, but people who exercise regularly do get some pretty great benefits. It can help maintain weight, aid in weight loss, bolster cardiovascular health and play a role in maintaining healthful blood lipid levels. It can also help with sleep and boost mood.